During operation, internal combustion engines generate various combustion by-products that are emitted from the engine in an exhaust stream. As such, various approaches may be utilized in order to reduce regulated emissions. In some examples, particulate emissions may be reduced by employing an aftertreatment system with a device such as a particulate filter in an exhaust passage of the engine. Further, turbochargers may be used in an engine system to increase a pressure of air supplied to the engine for combustion. In one example, the turbocharger includes a turbine coupled in an exhaust passage of the engine which at least partially drives a compressor via a shaft to increase the intake air pressure.
Over time, a particulate load of the particulate filter may increase such that regeneration of the particulate filter needs to be carried out to clean the particulate filter so that a backpressure on the engine does not increase, for example. The inventors herein have recognized when the particulate filter is positioned downstream of the turbine of the turbocharger in the exhaust passage, an exhaust gas temperature upstream of the particulate filter and downstream of the turbine may not be high enough to passively regenerate the particulate filter. Thus, active regeneration may be carried out by injecting fuel upstream of the particulate filter or heating the particulate filter via a heater, for example. In such an approach, efficiency of the system may be reduced due to increased fuel consumption and/or a cost of the system may be increased due to addition of components such as the heater.